#include<fstream>
#include<string>

using namespace std;

ifstream is("trie.in");
ofstream os("trie.out");

struct TRIE
{
	int nr_cuv;
	int nr_fii;
	TRIE* Next[27];
};
TRIE* Root;

void Add(string w, TRIE* T);
void Remove(string w, TRIE* T);
int Count(string w, TRIE* T);
int Prefix(string w, TRIE* T);


int main()
{
	int op;
	string w;
	Root = new TRIE();
	while (is >> op >> w)
	{
		switch (op)
		{
		case 0: Add(w, Root); break;
		case 1: Remove(w, Root); break;
		case 2: os << Count(w, Root) << '\n'; break;
		case 3: os << Prefix(w, Root) << '\n'; break;
		}
	}
	is.close();
	os.close();
	return 0;
}
void Add(string w, TRIE* T)
{
	if (w == "")
	{
		T->nr_cuv++;
		return;
	}
	if (T->Next[w[0] - 97] == NULL)
	{
		T->Next[w[0] - 97] = new TRIE();
		T->nr_fii++;
	}
	Add(w.substr(1), T->Next[w[0] - 97]);
}
void Remove(string w, TRIE* T)
{
	if (w == "")
	{
		T->nr_cuv--;
		return;
	}
	Remove(w.substr(1), T->Next[w[0] - 97]);
	if (T->Next[w[0] - 97]->nr_cuv == 0 && T->Next[w[0] - 97]->nr_fii == 0)
	{
		T->Next[w[0] - 97] = NULL;
		T->nr_fii--;
		return;
	}
}
int Count(string w, TRIE* T)
{
	if (T == NULL)
		return 0;
	if (w == "")
		return T->nr_cuv;
	return Count(w.substr(1), T->Next[w[0] - 97]);
}
int Prefix(string w, TRIE* T)
{
	if (T->Next[w[0] - 97] == NULL || w == "")
		return 0;
	return Prefix(w.substr(1), T->Next[w[0] - 97]) + 1;
}